Fungicidal mixtures

ABSTRACT

A fungicidal synergistic mixture containing a) a compound of the formula I   &lt;IMAGE&gt; I  where the substituents have the following meanings: R1 is a phenyl radical which can carry one to three of the following groups: cyano, halogen, C1-C4-alkyl, C1-C2-haloalkyl and C1-C4-alkoxy, or a pyrimidyl radical which can carry a C1-C3-alkyl group and/or a phenoxy group, the phenoxy group in turn being able to carry one to three of the following radicals: cyano, halogen, C1-C4-alkyl, C1-C2-haloalkyl and C1-C4-alkoxy, A is oxygen or oxymethylene (-OCH2-); X is CH or N, is oxygen or NR2, R2 being hydrogen, C1-C3-alkyl or C1-C3-alkoxy, and b) a pyrimidine derivative of the formula II   &lt;IMAGE&gt; II  where R is methyl, propyn-1-yl or cyclopropyl, in a synergistically active amount, is described.

This is a division of application Ser. No. 08/305,396, filed on Sep. 13,1994, now U.S. Pat. No. 5,508,283.

The present invention relates to a fungicidal mixture which contains

a) a compound of the formula I ##STR3## where the substituents have thefollowing meanings:

R¹ is a phenyl radical which can carry one to three of the followinggroups: cyano, halogen, C₁ -C₄ -alkyl, C₁ -C₂ -haloalkyl and C₁ -C₄-alkoxy, or a pyrimidyl radical which can carry a C₁ -C₃ -alkyl groupand/or a phenoxy group, the phenoxy group in turn being able to carryone to three of the following radicals: cyano, halogen, C₁ -C₄ -alkyl,C₁ -C₂ -haloalkyl and C₁ -C₄ -alkoxy,

A is oxygen or oxymethylene (--OCH₂ --);

X is CH or N,

Y is oxygen or NR², R² being hydrogen, C₁ -C₃ -alkyl or C₁ -C₃ -alkoxy,and

b) a pyrimidine derivative of the formula II ##STR4## where R is methyl,propyn-1-yl or cyclopropyl, in a synergistically active amount.

The invention additionally relates to processes for combating harmfulfungi using the compounds I and II and synergistic mixtures containingthem and to the use of the compounds I or the compounds II for theproduction of mixtures of this type. Compounds of the formula I, theirpreparation and their action against harmful fungi are disclosed in theliterature (EP-A 253 213, EP-A 382 375, EP-A 398 692).

The pyrimidine derivatives II, their preparation and their actionagainst harmful fungi are likewise known [R=methyl: DD-A 151 404 (commonname: pyrimethanil); R=1-propynyl: EP-A 224 339 (common name:mepanipyrim); R=cyclopropyl: EP-A 310 550].

With respect to a decrease in the application rates and an improvementin the spectrum of action of the known compounds, the present inventionis based on mixtures which, with a decreased total amount of appliedactive compounds, have an improved action against harmful fungi(synergistic mixtures).

Accordingly, the mixtures defined at the beginning have now been found.It has additionally been found that, with simultaneous joint or separateapplication of the compounds I and the compounds II or with applicationof the compounds I and the compounds II successively, harmful fungi canbe combated better than with only the compounds I or II.

With respect to the C═X double bond, the compounds of the formula I canbe present in the E configuration or the Z configuration (with respectto the groups OCH₃ and CO--YCH₃). Accordingly, they can be used in themixture according to the invention either as pure isomers or as an E/Zisomer mixture. Preferably, the E/Z isomer mixture or the E isomer isused, in many cases the E isomer being particularly preferred.

Because of the basic character of the NH group, the pyrimidinederivatives of the formula II are able to form salts with inorganic ororganic acids or with metal ions.

Examples of inorganic acids are hydrohalic acids such as hydrofluoricacid, hydrochloric acid, hydrobromic acid and hydriodic acid, sulfuricacid, phosphoric acid and nitric acid.

Suitable organic acids are, for example, formic acid, carbonic acid andalkanoic acids such as acetic acid, trifluoroacetic acid,trichloroacetic acid and propionic acid as well as glycolic acid,thiocyanic acid, lactic acid, succinic acid, citric acid, benzoic acid,cinnamic acid, oxalic acid, alkysulfonic acids (sulfonic acids withstraight-chain or branched alkyl radicals having 1 to 20 carbon atoms),arylsulfonic acids or -disulfonic acids (aromatic radicals such asphenyl and naphthyl which carry one or two sulfonic acid groups),alkylphosphonic acids (phosphonic acids with straight-chain or branchedalkyl radicals having 1 to 20 carbon atoms), arylphosphonic acids or-diphosphonic acids (aromatic radicals such as phenyl and naphthyl whichcarry one or two phosphoric acid radicals), the alkyl or aryl radicalsbeing able to carry further substituents, eg. p-toluenesulfonic acid,salicylic acid, p-aminosalicylic acid, 2-phenoxybenzoic acid,2-acetoxybenzoic acid etc.

Suitable metal ions are in particular the ions of the elements of thesecond main group, in particular calcium and magnesium, of the third andfourth main group, in particular aluminum, tin and lead, and of thefirst to eighth sub-group, in particular chromium, manganese, iron,cobalt, nickel, copper, zinc and others. The metal ions of the elementsof the sub-groups of the fourth period are particularly preferred. Themetals in this case can be present in the different valencies applicableto them.

Preferably, for the provision of the fungicidal mixtures according tothe invention, compounds I are used where the substituents have thefollowing meanings:

R¹ is a phenyl radical which can carry one to three of the followinggroups: cyano, halogen, C₁ -C₂ -alkyl, C₁ -C₂ -haloalkyl and C₁ -C₂-alkoxy, or

a pyrimidyl radical which can carry a C₁ -C₂ -alkyl group and/or aphenoxy group, the phenoxy group in turn being able to carry one tothree of the following radicals: cyano, halogen, C₁ -C₂ -alkyl, C₁ -C₂-haloalkyl and C₁ -C₂ -alkoxy,

A is oxygen or oxymethylene (--OCH₂ --);

X is CH or N,

Y is oxygen or NR², R² being hydrogen, C₁ -C₂ -alkyl or C₁ -C₂ -alkoxy.

Particularly preferred fungicidal mixtures are those which containcompounds I where the substituents have the following meanings:

R¹ is a phenyl radical which can carry one to three of the followinggroups: halogen, methyl, trifluoromethyl and methoxy,

A is oxymethylene (--OCH₂ --),

X is CH or N,

Y is oxygen or NR², R² being hydrogen, methyl or methoxy.

Particularly preferred fungicidal mixtures are also those which containcompounds I where the substituents have the following meanings:

R¹ is a pyrimidyl radical, in particular a pyrimidine-4,6-diyl radical,which can carry a methyl group and/or a phenoxy group, the phenoxy groupin turn being able to carry one to three of the following radicals:cyano, halogen, methyl, trifluoromethyl and methoxy,

A is oxygen;

X is CH or N,

Y is oxygen or NR², R² being hydrogen, methyl or methoxy.

Particularly preferred mixtures are additionally those which contain acompound of the formula I where R¹ is 2-methylphenyl or2,5-dimethylphenyl, A is oxymethylene, X is N and Y is oxygen or NH.

In addition mixtures are preferred which contain a compound of theformula I where R¹ is 2-methylphenyl or 2,5-dimethylphenyl, A isoxymethylene, X is N and Y is NH.

Additionally mixtures are preferred which contain a compound of theformula I where R¹ is 6-{2-cyanophenoxy}pyrimidin-4-yl, A is oxygen, Xis CH and Y is oxygen.

With respect to utility as mixture components the compounds I.A, I.B andI.C are particularly preferred. ##STR5##

Preferably, in the preparation of the mixtures the pure active compoundsI and II are employed, to which, if needed, further active compoundsagainst harmful fungi or other pests such as insects, arachnids ornematodes, or alternatively herbicidal or growth-regulating activecompounds or fertilizers, can be admixed.

The mixtures of the compounds I and II and the simultaneous joint orseparate use of the compounds I and II are distinguished by anoutstanding action against a wide spectrum of phytopathogenic fungi, inparticular from the Ascomycetes and Basidiomycetes class. In some casesthey are systemically active and can therefore also be employed asfoliar and soil fungicides.

They have particular importance for combating a multiplicity of fungi onvarious crop plants such as cotton, vegetable plants (eg. cucumbers,beans and cucurbits), barley, grass, oats, coffee, maize, fruit plants,rice, rye, soybean, grape, wheat, decorative plants, sugar cane and amultiplicity of seeds.

In particular, they are suitable for combating the followingphytopathogenic fungi: Erysiphe graminis (powdery mildew) on cereals,Erysiphe cichoracearum and Sphaerotheca fuliginea on cucurbits,Podosphaera leucotricha on apples, Puccinia species on cereals,Rhizoctonia species on cotton and lawns, Ustilago species on cereals andsugar cane, Venturia inaequalis (scab) on apples, Helminthosporiumspecies on cereals, Septoria nodorum on wheat, Botrytis cinera (graymold) on strawberries and vines, Cercospora arachidicola on groundnuts,Pseudocercosporella herpotrichoides on wheat and barley, Pyriculariaoryzae on rice, Phytophthora infestans on potatoes and tomatoes,Plasmopara viticola on vines, Alternaria species on vegetables and fruitand also Fusarium and Verticillium species.

They can additionally be used in material protection (eg. woodpreservation), for example against Paecilomyces variotii.

The compounds I and II can be applied simultaneously jointly orseparately or successively, the sequence when applied separately ingeneral having no effect on the combating success.

The compounds I and II are customarily applied in a weight ratio of from10:1 to 0.1:1, preferably from 5:1 to 0.2:1, in particular from 3:1 to0.3:1.

The application rates of the mixtures according to the invention are,depending on the type of desired effect, from 0.01 to 3 kg/ha,preferably from 0.1 to 1.5 kg/ha, in particular from 0.4 to 1.0 kg/ha.The application rates in this case for the compounds I are from 0.01 to0.5 kg/ha, preferably from 0.05 to 0.5 kg/ha, in particular from 0.05 to0.2 kg/ha. The application rates for the compounds II arecorrespondingly from 0.1 to 1.0 kg/ha, preferably from 0.4 to 1.0 kg/ha,in particular from 0.4 to 0.8 kg/ha.

In seed-treatment, application rates of mixture of from 0.001 to 50 g/kgof seed, preferably from 0.01 to 10 g/kg, in particular from 0.01 to 8g/kg, are in general used.

If harmful fungi pathogenic to plants are to be combated, the separateor joint application of the compounds I and II or of the mixtures of thecompounds I and II is carried out by spraying or dusting the seeds, theplants or the soils before or after the sowing of the plants or beforeor after the emergence of the plants.

The fungicidal synergistic mixtures according to the invention or thecompounds I and II can be prepared, for example, in the form of directlysprayable solutions, powders and suspensions or in the form ofhigh-percentage, aqueous, oily or other suspensions, dispersions,emulsions, oil dispersions, pastes, dusting compositions, broadcastingcompositions or granules and applied by spraying, atomizing, dusting,broadcasting or watering. The application form is dependent on theintended use; in each case it should ensure as fine and uniform adispersion of the mixture according to the invention as possible.

The formulations are prepared in a manner known per se, eg. by additionof solvents and/or carriers. Inert additives such as emulsifiers ordispersants are customarily admixed to the formulations.

Suitable surface-active substances are the alkali metal, alkaline earthmetal or ammonium salts of aromatic sulfonic acids, eg. lignosulfonic,phenolsulfonic, naphthalenesulfonic and dibutylnaphthalenesulfonic acid,as well as of fatty acids, alkyl- and alkylarylsulfonates, alkyl-,lauryl ether and fatty alcohol sulfates, and also salts of sulfatedhexa-, hepta- and octadecanols or fatty alcohol glycol ethers,condensation products of sulfonated naphthalene and its derivatives withformaldehyde, condensation products of naphthalene or ofnaphthalenesulfonic acids with phenol and formaldehyde, polyoxyethyleneoctylphenol ether, ethoxylated isooctyl-, octyl- or nonylphenol,alkylphenol or tributylphenyl polyglycol ethers, alkylaryl polyetheralcohols, isotridecyl alcohol, fatty alcohol ethylene oxide condensates,ethoxylated castor oil, polyoxyethylene or polyoxypropylene alkylethers, lauryl alcohol polyglycol ether acetate, sorbitol esters,lignin-sulfite waste liquors or methylcellulose.

Powders, broadcasting and dusting compositions can be prepared by mixingor joint grinding of the compounds I or II or of the mixture of thecompounds I and II with a solid carrier.

Granules (eg. coated, impregnated or homogeneous granules) arecustomarily prepared by binding the active compound or the activecompounds to a solid carrier.

Fillers or solid carriers used are, for example, mineral earths such assilica gel, silicic acid, silicates, talc, kaolin, limestone, lime,chalk, bole, loess, clay, dolomite, diatomaceous earth, calcium sulfateand magnesium sulfate, magnesium oxide, ground plastics, and alsofertilizers such as ammonium sulfate, ammonium phosphate, ammoniumnitrate, ureas and plant products such as cereal flour, tree bark meal,wood meal and nutshell meal, cellulose powder or other solid carriers.

The formulations in general contain from 0.1 to 95% by weight,preferably from 0.5 to 90% by weight, of one of the compounds I or II orof the mixture of the compounds I and II. The active compounds are inthis case used in a purity of from 90% to 100%, preferably from 95% to100% (according to NMR spectrum or HPLC).

The compounds I or II or the mixtures or the corresponding formulationsare applied by treating the harmful fungi or the plants, seeds, soils,areas, materials or spaces to be kept free from them with a fungicidallyactive amount of the mixture, or of the compounds I and II in the caseof separate application. Application can be carried out before or afterattack by the harmful fungi.

It was possible to determine the synergistic effect of the mixturesaccording to the invention by the formula of S. R. Colby (Weeds 15,(1967) 20-22)

    E═X+Y-X×Y/100

the variables having the following meanings:

X is the measurable effect of the active compound I at an applicationrate [a]

Y is the measurable effect of the active compound II at an applicationrate [b]

E is the expected measurable effect of a mixture of the active compoundI at the application rate [a] and of the active compound II at theapplication rate [b].

The difference between the expected value E according to Colby and themeasured value shows whether synergism (potentiation of the effect orincrease in the action) or antagonism (weakening of the effect orreduction in the action) is present, or if both values agree, that onlyadditive effects have an influence.

It was possible to show the improved biological action of the mixturesin comparison with the individual substances by the following tests:

Puccinia recondita

Leaves of wheat seedlings (variety "Fruhgold") were treated with theaqueous active compound preparation. On the next day the treated plantswere dusted with spores of brown rust (Puccinia recondita) and theplants treated in this way were incubated for 24 h at 20°-22° C. and arelative atmospheric humidity of 90-95%. After a further 8 days at20°-22° C. and 65-70% relative atmospheric humidity the extent of fungaldevelopment was determined. Evaluation was carried out visually (data onthe infected leaves in %).

The potency was calculated according to the formula of Abbott asfollows:

Potency=[1-(% attack after treatment)/(% attack without treatment)]×100.

The results are compiled in the following tables:

    ______________________________________                                        Active          Application                                                                             Potency                                             compound        rate [ppm]                                                                              [Abbott]                                            ______________________________________                                        I.A             500       89                                                  I.A             250       78                                                  I.A             125       78                                                  I.A             100       78                                                  I.A             50        67                                                  I.A             25        11                                                  I.A             12.5      22                                                  Pyrimethanil    500       22                                                  Pyrimethanil    250       0                                                   Pyrimethanil    125       0                                                   Pyrimethanil    100       0                                                   Pyrimethanil    50        0                                                   Pyrimethanil    25        0                                                   Pyrimethanil    12.5      0                                                   Mepanipyrim     500       0                                                   Mepanipyrim     250       0                                                   Mepanipyrim     125       0                                                   Mepanipyrim     100       0                                                   Mepanipyrim     50        0                                                   Mepanipyrim     25        0                                                   Mepanipyrim     12.5      0                                                   ______________________________________                                    

The activities achieved with the mixtures according to the invention arecompiled in the following tables:

    ______________________________________                                                                        Potency                                               Pyrimethanil  Potency   (according to                                 I.A [ppm]                                                                             [ppm]         (observed)                                                                              Colby)                                        ______________________________________                                        250     250           94        78                                            125     125           94        78                                            50      50            89        67                                            25      25            83        11                                            250     25            89        78                                            125     12.5          89        78                                            50      5             78        67                                            25      2.5           78        11                                            25      250           83        11                                            12.5    125           78        22                                            ______________________________________                                                                        Potency                                               Mepanipyrim   Potency   (according to                                 I.A [ppm]                                                                             [ppm]         (observed)                                                                              Colby)                                        ______________________________________                                        100     100           83        78                                            50      50            78        67                                            25      25            67        11                                            50      500           78        67                                            ______________________________________                                    

We claim:
 1. A fungicidal mixture containing in synergistic fungicidally effective amounts of:a) a compound of the formula IA or IB ##STR6## b) a pyrimidine of the formula II ##STR7## where R is propyn-1-yl, wherein the weight ratio of the compound IA or IB to the compound II is from 10:1 to 0.1:1.
 2. The fungicidal mixture of claim 1, wherein a) is a compound of the formula IA.
 3. The fungicidal mixture of claim 1, wherein a) is a compound of the formula IB.
 4. The fungicidal mixture as claimed in claim 1, wherein the weight ratio of the compound IA or IB to the compound II is from 5:1 to 0.2:1.
 5. The fungicidal mixture as claimed in claim 1, wherein the weight ratio of the compound IA or IB to the compound II is from 3:1 to 0.3:1.
 6. A process for combatting harmful fungi, which comprises treating the harmful fungi, their habitat or the plants, seeds, soils, areas, materials or spaces to be kept from them with from 0.01 or 3 kg/ha of a mixture containing in synergistic fungicidally effective amounts ofa) a compound of the formula IA or IB ##STR8## b) a pyrimidine of the formula II ##STR9## where R is propyn-1-yl, wherein the weight ratio of the compound IA or IB to the compound II is from 10:1 to 0.1:1.
 7. The process as claimed in claim 6, wherein the weight ratio of the compound IA or IB to the compound II is from 5:1 to 0.2:1.
 8. The process as claimed in claim 6, wherein the weight ratio of the compound IA or IB to the compound II is from 3:1 to 0.3:1. 